Bit for drilling wells



April 20, 1965 J. 5. GOODWIN 3,179,189

BIT FOR DRILLING WELLS Filed July 30, 1962 2 Sheets-Sheet 1 INVENTOR. Jaws. 6000M April 20, 1965 J. s. sooowm BIT FOR DRILLING WELLS 2 Sheets-Sheet 2 Filed July so, 1962 INVENTOR 5600 va m/.1: //v

a BY 44 I *3 AZZ'OZ/Vf/f United States Patent 3,179,189 BIT FOR DRILLING WELLS John S. Goodwin, Whittier, Calih, assignor to Globe Oil Tools Company, Los Nietos, Califi, a corporation of California Filed July 30, 1962, Ser. No. 213,522

3 Claims. (Cl. 175-340) This invention relates to the art of drilling oil, gas and other Wells and is particularly directed to improvements in a welldrilling bit of the type having rolling cutters and provided with nozzles for directing jets of fluid between the cutters.

In my prior Patent No. 2,875,984 granted March 3, 1959, there is disclosed a well-drilling bit of this general type and having a segmental body, each body segment having a trunnion at its lower end and a toothed cutter mounted to turn on the trunnion. The three body segments substantially surround a separate fluid distributor or manifold which is hollow and which has an upper circular wall defining an entrance opening for drilling fluid. Three lateral hollow wings project radially from thelower portion of the hollow member and each wing has an opening through which drilling fluid escapes. The separate distributor member thus has one entrance opening and three discharge openings leading therefrom. In the commercial form of the device shown in my prior patent the central hollow fluid distributor or manifold is constructed as a metal casting while the three body segments are metal forgings.

It is an important object of the present invention to provide a jet bit construction of the same general type disclosed in my priorpatent, but constructed in a manner to eliminate the hollow fluid distributor or manifold, thereby permitting reduction in the overall axial height of the bit assembly. The reduction in height improves the structural strength and rigidity of the bit body, and furthermore reduces the amount of welding necessary to join together the segments of the body.

Another object is to provide a structural member in the. form of ametal slab extending transversely of the body axis and joined integrally to each of the body segments by welding. An advantage of this construction is that no hollow manifold member is necessary and instead a fluid distribution cavity is formed by the body segments themselves, and with the metal slab forming the lower end of such cavity.

Other and more detailed objects and advantages will appear hereinafter.

In the drawings:

FIGURE 1 is a longitudinal sectional view showing a preferred embodiment of this invention, the cutters and thebit-carrying sub being shown in phantom lines;

FIGUREZ is a front elevation of one of the body segments prior to assembly.

FIGURE 3 is a perspectiveview of the metal slab which joins the three body segments and which provides a support for three jet nozzles.

FIGURE 4 is a fragmentary view taken in the direction of the lines 4*4 as shown in FIGURE 1.

FIGURE 5 is a transverse sectional view taken substantially on the lines 5--5 as shown in FIGURE 1.

FIGURE 6 is a transverse sectional view taken substantially on the lines 6-6, as shown in FIGURE 1.

FIGURE 7 is a rear elevation of one of the body segments, prior to assembly.

FIGURE 8 is a side elevation of one of the body segmerits showing how the bearing-contacting surfaces on the integral trunnion have unrestricted access radially of the trunnion so that conventional turning and grinding tools may be employed.

Referring to the drawings, the bit body generally designated 10 includes the three body segments 11, 12, and 13. These body segments are formed of steel forgings and are essentially duplicates. Each body segment is provided with a coupling section 14, an intermediate section 15, and a depending leg section 16 provided with an integral trunnion 17. A metal structural member in the form of a transverse slab Zll engages the intermediate portion 15 of each of the body segments 11, 12, and 13 and forms the lower end of the fluid distribution cavity 21 defined between the coupling sections 14 of the upright body segments 11, 12, and 13. This cavity 21 is provided at the lower end of the central fluid passage 22.

Each of the body segments is provided with a .downward facing shoulder 25 which rests against the upper surface 26 on the structural member 20. The outer Wall 23 on the slab 20 is tapered downward and outward and is received within the inner surfaces 24 on the body segments, which surfaces 24 are also tapered downward and outward. A central inwardly directed rib or boss 27 on each body segment fits within a shallow recess or groove 23 provided on the member 20. This member 20 is thus Y-shaped in plan view.

Each of the three arms of the Y-shaped member 20 is provided with a separate opening 30 which extends downward through the member and at a slight diverging angle from the central axis of the bit assembly. Each opening 36 may be provided with a jet nozzle assembly generally designated 31. Each assembly 31 may include a nozzle 32 held in place by a threaded retainer ring 33 and sealed by means of an O-ring 34.

Prior to assembly of the body segments 11, 12, and 13, the trunnion surfaces 36, 37, and 38 are machined and ground to provide inner races for the bushing 39, roller bearings 40 and for the ball thrust bearings 41. FIGURE 8 shows that the construction of the individual body segments is such that unrestricted radial access to the surfaces 36, 37, and 38 is obtained. Thus a large diameter efficient grinding wheel 42 may be used in a conventional manner to grind the surface 38, while the body segment is turned on centers 43 and 44.

A toothed cutter is rotatably mounted on each of the trunnions 17. The balls 41 are introduced through bore 46, and the bore is subsequently closed by the plug 47 and weld metal .48. A central disk 49 serves as an end thrust bearing.

After the toothed cutters are installed on the trunnion 17, the body segment 11, 12, and 13 are positioned to encompass-the Y-shaped member 20. The lower outer edges of the member 20 are joined touthe body segments .11, 12, and 13 by weld metal deposits 50, 51, and 52 (see FIGURE 6). Weld metal deposits 57, 58, and .59 also join the outer projecting portions of the member 20 to the body sections (see FIGURE 4).- External weld metal deposits join adjacent edges of the body segments above the locations of the weld metal deposits 59. Radial faces 62 on adjoining body segments meet in surface contact and internal weld metal deposits 63 join together adjacent coupling sections 14 of the body segments 11, 12, and 13. An alignment pin 65 may be mounted on the coupling section 14 of each body segment and positioned to be received within a corresponding hole 66 in an adjacent body section, in order to hold parts in position about the central member 20 while the weld metal deposits are being made. The welds 50, 51, 52, 57, 58, 59 and 6t) preventlfluid leakage from the fluid distribution cavity 21, and the drill collar sub 68 seals the coupling section 14 down to the shoulder 69.

After welding, the nozzle assemblies 31 are installed in place on the member 20. Drilling fluid admitted tothe distribution cavity 21 through the central passage 22' passes outward through the openings 30 and through the nozzles 32 in the form of jet streams, and the position and angle of the nozzle assemblies 31 is such that the jet streams are directed downward and outward between the cutters 45 and against the formation engaged by the cutters.

The upper portion of the coupling section 14 of the body is provided with tapered external threads 67 by which'the jet bit assembly may be connected to the drill collar sub 68 at the lower end of the rotary drill string, in the conventional manner. 7

Having fully described my invention it is to be understood that I am not to be limited to the details herein set forth but that my invention is of the full scope of the appended claims.

I claim:

1. In a well drilling bit, the combination of: a body comprising a plurality of duplicate upright metal body segments, each segment having a coupling section, an intermediate section, and a dependnig leg section provided with a trunnion on its lower end, the depending leg section of each body segment being circumferentially spaced from the others, a cutter rotatably mounted on each trunnion, said coupling sections co-operating to form a central axial fluid passage and an enlarged fluid distribution cavity therebelow, said intermediate section having inner walls which taper downwardly and outwardly, a metal slab extending transversely of the body segments below the coupling sections and engaging the intermediate section of each upright body segment to define the lower end of said fluid distribution cavity, the metal slab having outer walls which taper downwardly and outwardly for reception within said inner walls of said intermediate section, weld metal joining said metal slab to each of said intermediate sections of said body segments to provide structural interconnection and to prevent fluid leakage from said fluid distribution cavity, and said metal slab having a plurality of separate passages extending therethrough for directing streams of fluid downwardly and outwardly between vthe cutters, the passages having separate circumferentially spaced entrance openings in said slab, each opening communicating with said fluid distribution cavity.

2. In a Well drilling bit, the combination of: a body comprising a plurality of duplicate upright metal body segments, each segment having a coupling section, an intermediate section, and a depending leg section provided with a trunnion on its lower end, the depending leg section of each body segment being circumferentially spaced from the others, a cutter rotatably mounted on each trunnion, said coupling sections co-operating to form a central axial fluid passage and an enlarged fluid distribution cavity therebelow, said intermediate section having a downwardfacing shoulder and having inner walls below the shoulder which taper downwardly and outwardly, a metal slab extending transversely of the body segments below the coupling sections and engaging under the shoulder of the intermediate section of each upright body segment to define the lower end of said fluid distribution cavity, the metal slab having outer walls which taper downwardly openings in said slab, each opening communicating with said fluid distribution cavity.

3. In a well drilling bit, the combination of: a body comprising a plurality of duplicate upright metal body segments, each segment having a coupling section, an intermediate section, and a depending leg section provided with a trunnion on its lower end, the depending leg section of each body segment being circumferentially spaced from the others, each trunnion having an annular bearing race, a cutter rotatably mounted on each trunnion, said coupling sections co-operating to form a central axial fluid passage and an enlarged fluid distribution cavity therebelow, said intermediate section having a downwardfacing inwardly projecting shoulder, the axis of each trunnion being inclined sufliciently and the inward projection of the shoulder being so small as to permit unlimited radial access to said trunnion bearing race prior to installation of the cutter and assembly of the segments, said intermediate section also having inner walls below the shoulder whichtaper downwardly and outwardly, a metal slab extending transversely of the body segments below the coupling sections and'engaging under the shoulder of the intermediate section of each upright body segment to define the lower end of said fluid distribution cavity, the metal slab having outer walls which taper downwardly and outwardly for reception within said inner walls of said intermediate section, weld metal joining said metal slab to each of said intermediate sections of said body segments to provide structural interconnection and to prevent fluid leakage from said fluid distribution cavity, and said metal slab having a plurality of separate passages extending therethrough for directing streams of fluid downwardly and outwardly between the cutters, the passages having separate circumferentially spaced entrance openings in said slab, each opening communicating with said fluid distribution cavity.

References Cited by the Examiner UNITED STATES PATENTS 2,200,482 5/ 40 Winslow -340 2,216,894 10/40 Stancliff 175-340 X 2,803,436 8/57 McEachern 175-340 2,815,928 12/57 Bodine 175-340 X 2,875,984 *3/59 Goodwin 175-340 2,885,185 5/59 Sartor' 175-340 2,885,186 5/59 Hammer 175-340 CHARLES E. OCONNELL, Primary Examiner, 

1. IN A WELL DRILLING BIT, THE COMBINATION OF: A BODY COMPRISING A PLURALITY OF DUPLICATE UPRIGHT METAL BODY SEGMENTS, EACH SEGMENT HAVING A COUPLING SECTION, AN INTERMEDIATE SECTION, AND A DEPENDING LEG SECTION PROVIDED WITH A TRUNNION ON ITS LOWER END, THE DEPENDING LEG SECTION OF EACH BODY SEGMENT BEING CIRCUMFERENTIALLY SPACED FROM THE OTHERS, A CUTTER ROTATABLY MOUNTED ON EACH TRUNNION, SAID COUPLING SECTIONS CO-OPERATING TO FORM A CENTRAL AXIAL FLUID PASSAGE AND AN ENLARGED FLUID DISTRIBUTION CAVITY THEREBELOW, SAID INTERMEDIATE SECTION HAVING INNER WALLS WHICH TAPER DOWNWARDLY AND OUTWARDLY, A METAL SLAB EXTENDING TRANSVERSELY OF THE BODY SEGMENTS BELOW THE COUPLING SECTIONS AND ENGAGING THE INTERMEDIATE SECTION OF EACH UPRIGHT BODY SEGMENT TO DEFINE THE LOWER END OF SAID FLUID DISTRIBUTION CAVITY, THE METAL SLAB HAVING OUTER WALLS WHICH TAPER DOWNWARDLY AND OUTWARDLY FOR RECEPTION WITHIN SAID INNER WALLS OF SAID INTERMEDIATE SECTION WELD METAL JOINING SAID METAL SLAB TO EACH OF SAID INTERMEDIATE SECTIONS OF SAID BODY SEGMENTS TO PROVIDE STRUCTURAL INTERCONNECTION AND TO PREVENT FLUID LEAKAGE FROM SAID FLUID DISTRIBUTION CAVITY, AND SAID METAL SLAB HAVING A PLURALITY OF SEPARATE PASSAGES EXTENDING THERETHROUGH FOR DIRECTING STREAMS OF FLUID DOWNWARDLY AND OUTWARDLY BETWEEN THE CUTTERS, THE PASSAGES HAVING SEPARATE CIRCUMFERENTIALLY SPACED ENTRANCE OPENINGS IN SAID SLAB, EACH OPENING COMMUNICATING WITH SAID FLUID DISTRIBUTION CAVITY. 